## EOS get started and input examples

Equation of State (EOS) here calculates the energies of the most stable structures as a function of volume. Users can refer to Figure 4 of the [dpgen CPC paper](https://www.sciencedirect.com/science/article/pii/S001046552030045X?via%3Dihub) for more information of EOS.

#### An example of the input file for EOS by VASP:

```json
{
  "structures": [
    "confs/mp-*",
    "confs/std-*",
    "confs/test-*"
  ],
  "interaction": {
    "type": "vasp",
    "incar": "vasp_input/INCAR",
    "potcar_prefix": "vasp_input",
    "potcars": {
      "Al": "POTCAR.al",
      "Mg": "POTCAR.mg"
    }
  },
  "properties": [
    {
      "type": "eos",
      "vol_start": 0.9,
      "vol_end": 1.1,
      "vol_step": 0.01
    }
  ]
}
```

`vol_start` is the starting volume relative to the equilibrium structure, `vol_step` is the volume increment step relative to the equilibrium structure, and the biggest relative volume is smaller than `vol_end`.